What is actually in the number on the quote
The price you enter into the payback worksheet is only meaningful if you know what it buys. Two quotes for the same pack can include different work, and a lower price can be one that has left some of that work for later; this site has no price data to say how large such gaps are.
The lines a quote should name
The pack itself and its inverter. Some systems integrate the inverter into the battery enclosure and some use a separate hybrid unit that also handles the array. Which architecture you are being sold changes what happens if one part fails and whether the array can run without the grid.
Mounting and enclosure work. Wall or floor mounting, seismic bracing where required, and any weather protection for an outdoor installation.
Interconnection paperwork. The utility application, the permit, and the inspection. These take weeks and the timing matters wherever an incentive or a credit turns on a placed-in-service date.
Commissioning and monitoring setup. Configuring the dispatch mode is not a formality: a pack set to reserve most of its capacity for outages will not earn the arbitrage savings the quote may be advertising, and a pack cycled daily will reach its warranty cycle count sooner. Ask which mode the savings figure assumes.
The lines that quietly go missing
The critical-load subpanel. A pack delivering 7.08 kW [1] may not carry everything a house can draw at once, so a backup design can separate the circuits you want backed up onto their own panel. That is electrical work with its own labour and materials; check whether each quote includes it.
Service or panel upgrades. An older main panel with no spare capacity may need replacing before anything else can be connected. That can surface after signing if nobody checks first, so ask about it explicitly rather than hoping.
Conduit distance. A battery on the far side of a house from the panel is a materially different job from one mounted beside it. Where the pack is going changes the price, and a quote produced without a site visit has guessed.
Changes to the existing array or inverter. If you are adding storage to an existing solar installation and want the array to keep producing with the grid down, ask whether the quote includes any wiring or inverter changes that design needs, and what each costs.
Tariff and interconnection consequences. Not a cost line, but it changes what the battery is worth, because the export credit sets the value of every kilowatt-hour the pack keeps back. Whether adding storage changes your export arrangement is set by your utility’s interconnection rules, which this site has not sourced, so ask in writing whether your export arrangement survives the installation.
Making two quotes comparable
Reduce each to the same three facts before comparing anything. Usable kilowatt-hours, not nameplate — the packs on this site publish 5.0 kWh [3] and 10.0 kWh [2] usable, and a quote quoting nameplate is describing a smaller machine than it appears. Continuous kilowatts, which decides what can run during an outage. And whether the critical-load panel is in or out.
Quoted from the source document, retrieved 2026-08-06
“It has a total usable energy capacity of 5.0 kWh, and features six embedded grid-forming microinverters and 3.84 kW of continuous power”
Two things in that line are worth carrying into a quote comparison: the maker states USABLE capacity rather than nameplate, so it is a figure you can compare directly against a rival specification without a haircut — and the grid-forming hardware it names is what allows an installation to run detached from the grid, which is a capability the pack can have while the installation around it still cannot use it.
Then ask for the scope exclusions in writing. A quote with an explicit exclusion list is more trustworthy than one without, because the second kind has the same exclusions and has simply not told you about them yet.
Finally, ask what dispatch mode the savings figure assumes, and compare it against the mode you actually want. A backup-first configuration that keeps the pack near full is incompatible with an arbitrage savings estimate, so check that a quote does not offer both at once.
- Put the price inOnce you know what it buys, the worksheet does the rest.
- Check the size is rightThe evening sets a ceiling; check whether the quoted pack is above it.
- Check the warranty termsCycle count, term, and which one your usage reaches first.
Questions this page gets asked
Why can two quotes for the same battery differ?
Check scope before hardware. A critical-load subpanel, an electrical service upgrade, a long conduit run, a roof-to-garage cable path, permit and inspection fees, and whether the array is rewired to keep producing during an outage are each line items that can be present in one quote and silently absent from another. This site holds no installed-cost data, so it cannot say how much of a given gap scope explains; comparing the scope line by line is how you find out.
What is a critical-load panel and do I need one?
It is a second small panel holding only the circuits you want backed up, so the battery serves those rather than trying to carry the whole house. Whether your installation needs one depends on how the installer designs the backup and on the rules that apply to your home, which this site has not sourced. If a quote promises backup and shows no critical-load panel or equivalent, ask how the backed-up circuits are separated.
What is islanding and why does it matter?
Islanding is the ability to disconnect from the grid and keep generating safely on your own. Without it, the array shuts down along with everything else during an outage and the battery gets no recharge. If multi-day resilience is the reason you are buying, ask about it alongside capacity: capacity sets how much energy is stored, and islanding decides whether the array can refill it during an outage.
Why does this site not publish an average installed price?
Because we could not obtain one worth citing. The national dataset that tracks installed prices was unreachable from our machine, the laboratory report page refuses non-browser clients, and the remaining sources are marketing pages citing each other. An average we invented would silently determine every figure downstream of it, so there is a blank instead.
Provenance for every figure printed above
s4.enphase_10c.continuous_kw— Enphase Energy product page — https://enphase.com/store/storage/iq-battery-10c (retrieved 2026-08-06)s4.enphase_10c.usable_kwh— Enphase Energy product page — https://enphase.com/store/storage/iq-battery-10c (retrieved 2026-08-06)s4.enphase_5p.usable_kwh— Enphase Energy product page — https://enphase.com/store/storage/iq-battery-5p (retrieved 2026-08-06)